Cut the rolls into bite-sized cubes. Mix the poppy seeds and sugar. Layer the rolls, poppy seed sugar, sultanas and almonds alternately in a large serving bowl. Heat milk, dissolve butter in it, add bitter almond oil and rum as desired. Pour over the dry ingredients and mix well. Let it steep in the refrigerator for at least 12 hours.
Possibly take a little more milk, the mixture should be really moist.